U.S. Pat. No. 5,220,095 and U.S. Pat. No. 5,245,100 disclose a process for liquid phase alkylation of a hydrocarbon substrate with an olefinic alkylating agent in the presence of a fluorinated alkyl sulphonic acid catalyst supported on polar contact material.
U.S. Pat. No. 5,349,116 describes the use of triflic acid supported on a combination of aluminum borate and aluminum oxide as catalyst for the alkylation of alkane (preferably isobutane or isooctane) with olefins preferably 1-pentene or 1-hexene to obtain a product composition having a higher proportion in the middle distillate boiling range.